Managing Serviceguard Seventeenth Edition, First Reprint December 2009

CVM and VxVM Worksheet
You may find a worksheet such as the following useful to help you organize and record
your specific physical disk configuration. This worksheet is an example; blank
worksheets are in Appendix E (page 429).
=========================================================================
Disk Group Name: ______dg01_____________________
Disk Name: _____________________c1t2d0__________________________
Disk Name: _____________________c2t2d0__________________________
Disk Name: _____________________c3t2d0__________________________
Disk Name: _____________________________________________________
CFS DG Package Name: ___________SG-CFS-DG_1_____
CFS Volume, MP, and MP Pkg: _logdata_/mnt/lvol1_ SG-CFS-MP_1______
CFS Volume, MP, and MP Pkg: ______________________________________
Disk Group Name: ______dg02______________________
Disk Name: _____________________c1t3d0__________________________
Disk Name: _____________________c2t3d0__________________________
Disk Name: _____________________c3t3d0__________________________
CFS DG Package Name: ___________SG-CFS-DG_2_____
CFS Volume, MP, and MP Pkg: _hrdata__/mnt/lvol4_ SG-CFS-MP_2____
CFS Volume, MP, and MP Pkg: ____________________________________
Cluster Configuration Planning
A cluster should be designed to provide the quickest possible recovery from failures.
The actual time required to recover from a failure depends on several factors:
• The value of the cluster MEMBER_TIMEOUT.
See MEMBER_TIMEOUT under “Cluster Configuration Parameters ” (page 139)
for recommendations.
• The availability of raw disk access. Applications that use raw disk access should
be designed with crash recovery services.
• The application and database recovery time. They should be designed for the
shortest recovery time.
In addition, you must provide consistency across the cluster so that:
• User names are the same on all nodes.
• UIDs are the same on all nodes.
• GIDs are the same on all nodes.
• Applications in the system area are the same on all nodes.
• System time is consistent across the cluster.
• Files that could be used by more than one node, such as files in the /usr directory,
must be the same on all nodes.
Heartbeat Subnet and Cluster Re-formation Time
The speed of cluster re-formation depends on the number of heartbeat subnets.
134 Planning and Documenting an HA Cluster